get server ram with php

Question

Hi,

Is there a way to know the avaliable ram in a server (linux distro) with php (widthout using linux commands)?

edit: sorry, the objective is to be aware of the ram available in the server / virtual machine, for the particular server (even if that memory is shared).

Answer 1

it would still be limited by memory_limit...

no way that i know of to do this cross-platform, php-only way.

Answer 2

I don't remember having ever seen such a function -- its kind of out the scope of what PHP is made for, actually.

Even if there was such a functionnality, it would probably be implemented in a way that would be specific to the underlying operating system, and wouldn't probably work on both Linux and windows (see sys_getloadavg for an example of that kind of thing)

Answer 3

If you know this code will only be running under Linux, you can use the special /proc/meminfo file to get information about the system's virtual memory subsystem. The file has a form like this:

MemTotal:       255908 kB
MemFree:         69936 kB
Buffers:         15812 kB
Cached:         115124 kB
SwapCached:          0 kB
Active:          92700 kB
Inactive:        63792 kB
...

That first line, MemTotal: ..., contains the amount of physical RAM in the machine, minus the space reserved by the kernel for its own use. It's the best way I know of to get a simple report of the usable memory on a Linux system. You should be able to extract it via something like the following code:

<?php $fh = fopen('/proc/meminfo.txt');
$mem = 0;
while ($line = fgets($fh)) {
  $pieces = array();
  if ($preg_match('^MemTotal:\s+(\d+)\skB$', $line, &$pieces) {
    $mem = $pieces[1];
    break;
  }
}

echo "$mem kB RAM found"; ?>

(Please note: this code may require some tweaking for your environment.)

Answer 4

Using '/proc/meminfo' and getting everything into an array is simple:

<?php

function getSystemMemInfo() 
{       
    $data = explode("\n", file_get_contents("/proc/meminfo"));
    $meminfo = array();
    foreach ($data as $line) {
     list($key, $val) = explode(":", $line);
     $meminfo[$key] = trim($val);
    }
    return $meminfo;
}

?>

var_dump( getSystemMemInfo() );

array(43) {
  ["MemTotal"]=>
  string(10) "2060700 kB"
  ["MemFree"]=>
  string(9) "277344 kB"
  ["Buffers"]=>
  string(8) "92200 kB"
  ["Cached"]=>
  string(9) "650544 kB"
  ["SwapCached"]=>
  string(8) "73592 kB"
  ["Active"]=>
  string(9) "995988 kB"
  ...